Check the screenshots below. These have been claimed to be leaked screenshots of Symbian /Nokia Carla.

Nokianesia blog claims that they have received these screenshots from their reliable partner. So it seems that many features from N9’s Swipe OS and the keyboard from windows phone OS will make its way to Symbian with Carla.
They also mention that , this update is not coming to the 1st generation of Symbian^3 Devices like Nokia N8, E7, C7 and C6-01. This seems true as even our sources confirmed that Symbian^3 devices will get light version of Carla and not the full update.
Based on the screenshots, the new features coming with Carla are,
  • New on-screen qwerty keyboard (adopt from Windows Phone qwerty model)
  • New Lock screen without Unlock Button
  • New method (Swipe to unlock) to unlock the screen
  • New Version and New UI Music Player
  • New Interface for Option (Now with Blue button – Look alike on Meego Harmattan)
  • New Version Nokia Browser
  • Some UI Improvement on Nokia Browser

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